PET/CT Frequently Asked Questions

PET/CT

When used together, Positron Emission Tomography and Computed Tomography (PET/CT) combine information on anatomy (size and location of a tumor or mass) and metabolic function (cellular activity of a tumor or mass) into one, easy-to-read image.

Doctors use this test to accurately diagnose, stage and treat cancer, as well as diagnose Alzheimer's disease and heart disease earlier than other imaging methods and with higher diagnostic confidence than offered by PET or CT alone.

For more information about PET/CT, view the PET/CT Frequently Asked Questions (below). You may also visit WebMD.com and search "PET/CT."

What is a PET/CT scan?

When used together, Positron Emission Tomography and Computed Tomography (PET/CT) combine information on anatomy (size and location of a tumor or mass) and metabolic function (cellular activity of a tumor or mass) into one, easy-to-read image.

Doctors use this test to accurately diagnose, stage and treat cancer, as well as diagnose Alzheimer's disease and heart disease earlier than other imaging methods and with higher diagnostic confidence than offered by PET or CT alone.

How should I prepare for a PET/CT exam?

What is the weight limit for your equipment?

Factors such as a patient's body weight, body habitus and scan type may determine whether or not the scan can be performed. The weight limit for our PET/CT equipment at Day Kimball Hospital is 400 pounds.

What should I expect during the exam?

You will receive a small injection of FDG (sugar water with a radioactive tracer). You will sit or lie down on a comfortable chair or bed for 30 to 90 minutes while the FDG travels throughout your body.

After this time, the technologist will assist you to the scanner. The CT portion of the exam is completed first, followed by the PET portion. You may be asked to hold your breath for several seconds while the CT scan is performed.

It is important that you don't move for the duration of the exam. When the total scan is finished, the computers will produce images for the radiologist to review.

How long will the scan take?

Every PET/CT exam is different, but most patients can expect to be at the center for two to three hours. This includes the time needed for the injected tracer to distribute throughout your body, as well as the time you actually spend moving through the scanner. Your height and the area of the body being scanned determine the exact length of your exam.

What should I expect after the exam?

Once the total scan has been performed, you may resume daily activity. Even though the FDG will quickly leave your body, you can expedite the process by drinking plenty of water after your scan is complete.